The present invention relates to surface modification of fabricated or semifabricated low melting reactive metal parts, particularly of aluminum magnesium in elemental or alloy forms, and more particularly to producing changed physical or chemical properties on metal, e.g., hardened surfaces.
There are many known and long practiced methods for improving the resistance of surfaces of fabricated or semi-fabricated metal (including elements, alloys and compounds) to wear, galling, deformation, corrosion, heating and/or erosion. Such prior art and its limitations are elaborated in the above referenced U.S. applications which also disclose a method of laser melting and alloying a low or not substantially higher melting point coating with a higher melting point substrate to produce resistant surfaces in a way overcoming such limitations.
My U.S. Pat. Nos. 3,952,180 (sole) and 4,015,100 (with E. Locke) disclose, respectively, cladding and surface alloying methods overcoming above problems and I now disclose an improvement applicable to surface enhancing low melting reactive metal substrates by mixture of a coating therewith and/or melting it.
It is an important object of the present invention to provide an improvement in metal wear resistance protection and related arts in respect of extending the method capabilities of such art(s) and/or producing improved products and more particularly blending high melting point surface coating with a lower melting substrate to produce a modified surface in a high volume percentage, i.e. including above 50% of high melting coating material.
It is a further object of the invention to provide high density, low porosity, modified surface layers consistent with one or more of the preceding objects.
It is a further object of the invention to provide surface layer treatment which is tolerant of difficult geometries, including reentrants and remote surface regions, consistent with one or more of the preceding objects.
It is a further object of the invention to provide surface layering, without regard to electrical or magnetic field conditions which may exist in the region or surface to be treated or which may develop in the course of processing, consistent with one or more of the preceding objects.
It is a further object of the invention to utilize low cost base or workpiece materials, with respect to initial selection and quantity and in limitation of quantity of usage, consistent with one or more of the preceding objects.
It is a further object of the invention to minimize the costs in labor, materials and/or time of ancillary machining and/or heating steps related to surface layering, consistent with one or more of the preceding objects.
It is a further object of the invention to provide flexibility of process control consistent with one or more of the proceding objects.
It is a further object of the invention to minimize incidental effects on the substrate below the surface layer consistent with one or more of the preceding objects.
It is a further object of the invention to provide a surface layer with selectively coarse or fine microstructure consistent with one or more of the preceding objects.
It is a further object of the invention to provide minimal working time and related substrate preparation and post treatment time consistent with one or more of the preceding objects.